Nahānavagga

Vinayapiṭaka · Parivāra · Vol. 8 · Section 695

[695] Bathing naked, she commits two offences (āpatti): while she is bathing, in the act (payoga) there is an offence of wrong-doing (dukkaṭa); at the completion of the bath, an offence entailing expiation (pācittiya).

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 2 other places

Vol. 8 · Section 762 — Chattupāhnavagga
Vol. 8 · Section 347 — Surāmerayavagga